James Blish

“ Atel said succinctly. "The metal, of course, is useless, but the vacuum inside is steel-hard to them. Space crushing into space, and gouts of hard radiation bursting like blood from the contact. That's all we have now, that and a feeble energising process which sometimes seals off the foundations of the city. Walls, and clubs! Our last miserable recourses—and then—
"Then the space-beasts will own the Earth again." ”

“ Andreson growled. "How near through are you?"
"Almost. I'm not trying to hit the gallery, though it might be easier that way." Suddenly he became serious. "I'll tell you what, Ken. It's a new life we're going back to—a life where you and I can look back into the past whenever we want, and visit it, too, if we keep quiet about it. And it's a new world we're going back to, a world which is going to be given the levitator. That means free flight—not just flight in machines, but real flight, where one man can fly whenever, wherever he wants, without having to board a plane or pay a fare. ”

“ Andreson remembered again the picture of the deserted city, and despite the hot sun he felt the same chill.
"This planet you call Earth," Atel said, "has no life on its surface now with enough intelligence to count up to three. But after we had been here fifty-three of its years, we discovered that Earth has a civilization of its own all the same—inside." ”

“ The girl, who had been preceding them, stopped at the top of the stairwell and levelled a dainty finger at Atel. "Why don't you stop tormenting him because he's not a scientist?" she demanded angrily. "It isn't his fault! He's doing his best for us!"
Atel's eyebrows would have shot up, had he had any. "Certainly," he purred, with an ironical gesture. "I'm sure you understand my attitude, Mr. Andreson. As a non-scientist, you are more of a curiosity than a gift, and that is a disappointment to us. We shall try to make your stay here as comfortable—and as short—as possible." ”

“ Atel was not fighting another winged man. He was fighting an Earthman with a levitator. That scrap between the buildings—had Atel given such a buffeting to a Varan he would have knocked him and that would have been the end of it. But the levitator couldn't be knocked out, no matter what happened to the man operating it. It wouldn't fall unless it was set to fall.
There was something else, too. Birds fly because they're built for it—among other things they have a huge keel-like breastbone to which their flying muscles are anchored. But bats don't, and Andreson bet that the Varans didn't either. ”

“ A single figure, man-like, but borne aloft on taut, delicate wings which suggested a bat rather than a human, floated over the nearest of the towers. A quick glance revealed that all the paintings but one contained several of these shapes; the one exception was a field of stars with a torpedo streaking across it. ”

“ Atel spat out bitterly. "See the column of light inching out from the borer's nose? They are disintegrating a tunnel for their vacuum torpedoes. It's a slow-motion kind of warfare—but when one side wins constantly, it can't last forever. Feel the radiation?"
Andreson discovered that he was scratching. His skin felt as if he had a mild sunburn. "The boring mechanism?" he suggested.
"Right," Atel admitted, his tone grudging. "Matter-against-matter generates radiant heat. Space-against-space generates X-rays and worse. Deadly stuff! ”

“ For a while the neglect had nettled Andreson, and at the moment he definitely did not want to talk to Kimball. Jina interested him a good deal more.
But Jina was still dreaming of her picture of Earth, as it would be millions of years hence. Before Andreson could protest, she leapt into the air and soared after the trailing cigarette glow. He watched, grousing, while the little red spark halted in mid-air and did a short minuet. Finally he stood up, picked up the heavy torpedo of his own levitator, clipped the control box to his belt, climbed into the parachute-harness. ”

“ But we are decadent, and have lost the initiative to be the aggressors. The machines that accomplished the reversal of state for our ancestors have lain idle for a century in the bowels of our city. We no longer understand them. We are dying, first of all, of old age—the space-beasts are the accident that speeds us along the way. Shall I tell you what we use against them now?"
The girl stirred protestingly. Andreson looked at her, but she would not return the glance. Atel went on relentlessly. ”

“ Around the base of the dome proper a ledge or platform ran, upon which was more of the furniture-like stuff—evidently a sort of solarium. Extending outside the walls as well as inside, it gave the building the look of a giant in a plastic helmet. At the apex of the dome a gem, like a giant's diamond, was fixed, rotating slowly, catching the sunlight and sending a parade of rainbow hues over the seats banked far below.
"Starstone Chamber," the girl said. "Our council hall."
"It's beautiful. Not a place for stuffy-minded men, I'd say." ”

“ But so far we've found no mammals on this planet, except a few egg-laying ones that aren't even entirely warm-blooded yet; so you must be a considerable distance in our future. Furthermore, you're a time-traveller, which means that you know more than we do, for time is a problem we have never broken."
The girl shook her head slowly, all traces of her former laughter vanished. "It's no use, Atel. He's here by accident, and isn't a scientist."
"What's the matter?" Andreson said. ”

“ But this complete inversion of space-matter relationships was unknown to us. The space-beasts knew about it. They are bent on driving us from the Earth...."
Andreson felt his mind reeling into hysteria again. It was difficult enough to accept the spotless, shining glass chamber and the two winged Varese—but this story of an inside-out universe and its air-treading masters—if only John Kimball had been the one to hear it—
"Sometimes," Atel said reflectively, "I think the Varese have earned their defeat. There was a time when we were carrying the fight into the enemy's own cosmos. ”

“ A dozen legends chased through Andreson's mind at once. "Cave-dwellers of some sort? It hardly seems credible."
"No, not cave-dwellers. These aren't even solid, and they couldn't live in caves. They live in the Earth—in the rock itself, and all the way down to the core. They are—space-beasts. They move through solid matter just as you and I move through space, and are stopped by space as we are stopped by a solid wall. In the air, for instance, we're safe from them, for what is to us a thin gas is for them a viscous, almost rigid medium. In the oceans, we meet on equal terms ”

“ The rock dome was below him, not above! The space-beasts, who reacted to gravity in reverse, had imposed their environment upon the city. Only the solarium platform, which had been directly above where he had been standing on the catwalk, had saved him from mashing against the dome. He wondered if the Varan gunners had been able to hit any of the borers under these conditions. ”

“ Andreson demanded. "The beasts? Jina's right—it is ridiculous."
"Yes, the beasts," one of the Guardsmen said flatly. "You're a native of Earth, no matter what your Time, and so are they. You could easily be the vanguard of a raid."
Andreson's temper was already short from the buffeting he had taken. "There's not a shred of evidence for such a theory," he snapped.
"Unfortunately, there is," Atel purred. "We noticed a beast travelling through the foundations of the city, just below the energy barrier, and managed to trap it. ”

“ Do you think I'm such a fool? The Council is blind with sitting so long under the Starstone—but there are still a few of us who can see!"
"What with?" Andreson taunted. "You seem to be all mouth."
With a low snarl of rage, Atel plunged. His powerful wings furled tightly around his body, he dropped straight for the Earthman. In the dim light, Andreson saw his massive right arm reach back to his belt—he was drawing his vacuum club—
Andreson jammed the button home and shot skyward. ”

“ Atel continued evenly. "In a sort of borer—I suppose they thought of it as that—whose walls were invisible, its machinery a contorted group of vacancies in a solid interior. But we destroyed the solid part, and they were crushed. It is hard to imagine how empty space could crush. But we have the law that two objects may not exist in the same space at the same time, and this seems to be its converse."
Andreson tried it out: two spaces cannot exist in the same—in the same what? Abruptly his head was whirling and in the vast distance the earth reeled and shuddered ”

“ The openings change shape as they move, and of course no natural pit does that. In their own universe, the hollow Earth bounded by its solid atmosphere, they are flying creatures, and their sense of gravity is the reverse of ours. ”

“ We seem alike, but we're not. The apes are my cousins; the bats are yours. You should stay with your own race, and have the children I could never give you. We have no real happiness to give each other. ”

“ Andreson's misfortune. But we are losing one battle, and can't afford to take on another. Our major question must be—How can we believe you?"
"One problem at a time," Kimball said. "About your present battle. I've watched your whole history, and I know you're doomed to lose it. This city will be deserted in another century. But it will be an orderly retreat, and will result in the complete extermination of the space-beasts."
Atel's mouth drew down at the corners. "Obviously a fabrication. If we wiped out the beasts, why should we leave?" ”

“ I can show you how to build a time-coil. We'll just open a window onto Tomorrow Noon and let the sunlight stream in on your main converter. It's really quite simple once you know the principle."
"By the Jewel! Have you repealed the law of the conservation of energy?"
"Not at all. Just doesn't apply. Energy taken from one Time doesn't alter the total available in the continuum. Here, I'll show you." He pulled out a pencil. "Got any paper? No? Ken, do you still have that letter on you?"
"Here you are," said Andreson, handing it over. "I'm glad it's going to be good for something, anyhow." ”

“ Because you'll wipe them out with matter-bombs, set to fall into their universe in their state, and then explode into yours. The process will cause violent earthquakes on Earth's surface—it'll change the whole climate of the planet, wipe out the giant reptiles, start the tiny mammals on their long upward climb toward the species Ken and I represent. Your civilization wouldn't survive such an upheaval. ”

“ Our power, our air ... cut off!"
"They've worked a miracle," the girl said with unwilling respect. "The beasts are scientists—we knew that in the beginning. Don't you see, Atel? They'll use that dome to get above the city! And their borers, too—"
Indecisively Atel spread his wings half-way. "We can't carry this Earthman about the city now," he said. "Jina, go to your post. I'll take him back to my rooms."
"But—" Andreson and the girl protested simultaneously.
"Need I remind you that I command this sector during emergencies, by Council order?" the Varan snapped. ”

“ Andreson took out his fountain pen and an unopened letter and walked toward the door. He must get the address of this place and attempt to locate the artist. John Kimball's inscription on the envelope reminded him that Johnny, though a scientist, dabbled in the arts and would be interested. He ripped open the flap, then stopped in mid-stride, ducked under the rayon cord to look at the spaceship scene.
In many ways this was the most wonderful of the lot. Even a night sky or a telescope field has no depth; it is merely a black surface containing spots of light ”

“ Atel—hold his other arm. If the beasts wear down our shield we will all be thrown on our heads again."
The Earthman allowed the Varans to take his elbows without any protest. He had a very vivid picture of himself buttered crimsonly over the inner surface of the rock arching above. Save the heroics for later, he thought.
He had imagined a Council meeting as a huge affair, with all the banked chairs filled; but actually there were only about twenty of the Varese present, plus the lone, mysterious Earthman. Andreson scanned the stranger's features eagerly as they approached. ”

“ After steadying himself against the wall, he made a slow circuit of the tower, stepping over the structural members of the platform cautiously. No doorways here—even a flying people usually enter floors from the top side. Returning, he eyed the upper edge of the catwalk doorway. It was an eight-foot opening, and he was exactly six feet tall; that left a margin of about six feet, which he might be able to jump. He wasn't in very good shape, and the platform didn't offer much of a starting run, but he'd have to chance it. ”